1. Technical Field
The present invention relates to a technique for controlling the amounts of light emitted from light emitting elements such as organic light-emitting diode (hereinafter, abbreviated as OLED) elements.
2. Related Art
In a light emitting device in which a plurality of light emitting elements are arranged, variation in the amount of light (luminance) among the light emitting elements causes a problem. In order to overcome this problem, for example, JP-A-2003-1118163 discloses a technique that measures the amounts of light emitted from light emitting elements beforehand and that corrects the amounts of light according to the result of measurement.
The characteristics of a light emitting element deteriorate at a speed in accordance with the amount of current supplied to the light emitting element. Therefore, when the amounts of current supplied to a plurality of light emitting elements are corrected according to the characteristics, as in the above-described publication, the characteristics of the light emitting elements deteriorate at different speeds. For example, when the light emitting element has a low luminous efficiency, correction is made to increase the current to be supplied to the light emitting element (that is, correction is made to increase the amount of emitted light). Consequently, deterioration of the characteristics proceeds more quickly than a light emitting element having a high luminous efficiency. When the speed at which the characteristics deteriorate varies among the light emitting elements, as described above, the variation in the characteristics increases with time.